Scheduled time for Public Observing: 9pm – 11pm

Solar System Objects:

The Moon: will be 25° high in the South at 9pm, and 82% illuminated, Waxing Gibbous phase. It’s position tonight is halfway between Jupiter to the West and Saturn to the East, both planets are easily visible and are the brightest objects in the area. An interesting feature to observe tonight is Sinus Iridium (The Bay of Rainbows). It’s a very large crater, 154 miles across, that was flooded with lava from Mare Imbrium.

Image copyright (c) Virtual Moon Atlas /

Planets: Jupiter and Saturn will both be visible, Jupiter will be getting low in the sky by 10pm. The position of their brightest satellites at 10pm is shown below. Jupiter’s four largest moons, Io, Europa, Ganymede, and Callisto are visible in binoculars, and Saturn’s moon Titan in almost any telescope.

Images courtesy of Starry Night (R) Orion Special Edition, Version: 6.2.3 kcEW, Imaginova (R) Corp.

Double Stars: A little to the West of Jupiter there’s an attractive multiple star called Graffias (Beta Scorpii). It’s about 530 light years distant, the 2 main components are separated by 2200 times the distance from the Earth to the Sun, and take about 16,000 years to orbit each other. There are other stars in the system making it at least quintuple, but they’re too close to the main components to see.

Star Charts and other Information:

A very useful monthly star chart can be downloaded here from, giving information on objects visible with the unaided eye, binoculars, or telescope.

For current astronomical events see Sky and Telescope Magazine’s “This Week’s Sky at a Glance”.